1. Field of the Invention
The present invention relates to an apparatus for removing and conveying a bag from a stack of bags.
2. Description of the Prior Art
DE 38 06 419 A1 discloses such an apparatus in which the bag to be removed is sucked against a conveyor belt which then conveys the bag to a predefined position. However the further handling possibilities of the so conveyed bag are very limited since the bag has to be released at a predefined position. The operating area of such a device is therefore very small and the throughput capacity of these known apparatuses are rather low.
In known apparatuses of this kind the uppermost bags of a stack of bags stored in a bag hopper are removed by means of a (swivelable) gripper arm which is provided with a suction function, are lifted and thus separated from the remaining stack of bags.
It is known from GB 375.260 A to lift the uppermost bag of such a stack of bags by means of a vacuum gripper arm through the gaps of a chain conveyor, with the chains of the chain conveyor being connected with rods and the arrangement of rods being interrupted by one or several gaps. The uppermost bag is held for such a time until the entire bag is driven underneath by a revolving rod arrangement which is separated by the gaps. The bag is then released and conveyed by the chain conveyor to a position for further processing.
The disadvantage of these known apparatuses is the fact that only very limited throughput capacities are possible because there are only very few gaps in the chain conveyor and that the chain conveyor can only be driven at low speed because the bags to be conveyed only rest on the chain conveyor, which leads to the danger for particularly light bags that they will fall down due to the air stream produced by the chain conveyor.
Solutions are also known where the bag is swiveled by a vacuum gripper arm from a horizontal plane to a vertical plane from where it is conveyed by means of further conveying means to an end position (e.g. a filling station).
The disadvantage also arises in said known solutions of a very low throughput due to the mechanical structure of such a gripper. Moreover, the conveyance of the bag to be removed to a horizontal position with a vacuum gripper can only be realized in a very complicated manner.